Synonyms for Untouchable (same or very similar meaning)
WordNet sense 1 (belongs to lowest social and ritual class in India):
Harijan
WordNet sense 2 (impossible to assail):
unassailable
WordNet sense 3 (incapable of being transgressed or dishonored):
inviolable
WordNet sense 4 (not permitted):
impermissible
WordNet sense 5 (ritually unclean or impure):
impure, unclean
WordNet sense 6 (not capable of being obtained):
inaccessible, unobtainable, unprocurable
WordNet sense 7 (not available or accessible or at hand):
unavailable
From the ODE community, based on WordNet
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